The terms “distal” and “proximal” in the context of the present text refer to the direction of the end-portions of the dilation device positioned in the cervix canal in regards to the inner and outer orifices of the cervix canal, respectively.
Approximately 3 million cervical canal dilations are performed annually in the United States for the purpose of intra-uterine procedures. These procedures include: abortions, hysteroscopies and other curettages. Cervical canal dilation allows medical practitioners greater access to the inside of the uterus in order to insert surgical tools for the completion of intra-uterine procedures.
Presently there are primarily two mechanical techniques for dilating the cervix. The first technique is the insertion of Laminaria (dry, sterile seaweed) or synthetic osmotic dilators into the cervix. When either Laminaria or a synthetic osmotic dilators come into contact with body fluids, it expands and enlarges the opening of the cervix. Often, this process requires two patient-visits and approximately 10-12 hours for sufficient dilation to occur.
The second technique, referred to as Hegar dilation, involves the insertion and removal of metal rods that are graduated in increasing diameter. This process is painful, requires the use of anesthesia, and is associated with a risk of uterine and cervix damage and cervical incompetence.
In addition to the two primarily cervix dilating techniques mentioned above there are techniques in which cervix dilating is achieved by the use of inflated balloons.
In U.S. patent application 2007/0288051 Beyer et al. disclose a cervical canal dilator device in which an elongate tubular or cylindrical shaft is inserted into the cervix canal. The shaft is provided with internal cavities that communicate with several dilation-balloons in such a manner as to permit the separate inflation of the balloons. A balloon is positioned on the distal end of the shaft and anchors the dilator against the bottom of the cervix when inflated after the dilator is inserted in a cervix and the remaining dilation balloons being positioned between the distal and proximal ends so as to effect optimum dilation of the cervical canal when inflated.
In PCT publication WO2004/052185 Foltz et al. disclose a cervical canal dilating device and method that includes a plastic shaft, and two inflatable members. The shaft can range from being rigid to being highly flexible. One of the inflatable members is fabricated of a non-elastic material and is configured to have a maximum inflatable diameter. The second inflatable member is configured to have a predetermined maximum inflatable diameter. A control system includes means for measuring pressure configured for at least monitoring the pressure of the second inflatable member. In deploying, the dilating device is inserted into the cervical canal. The first inflatable member is expanded in the uterus. The second inflatable member is positioned in the cervical canal and gradually inflated to a predetermined maximum diameter.
The mentioned cervix dilating devices are cumbersome to use and do not give the professional operator the ability to readily adjust the procedure to the physiological requirement of any individual treated woman.
The use of inflated balloons for the sealing of the cervix canal is described in the devices disclosed in the U.S.-patent and U.S. patent application given below:
In U.S. Pat. No. 4,976,692 Atad discloses a device in which two distantly positioned balloons are connected to a catheter that is inserted into the cervix canal. When the catheter is inserted the balloons are inflated so as to cover and seal the internal and external opening of the cervix canal. An opening located between the balloons enables confined input of medical gel or solution through catheter into the cervix canal. Atad's device relates to widening of the cervix canal prior to birth giving and does not relate and is not able to preform controlled cervical canal dilation procedures in treated patients.
In U.S. patent application 2002/0111602 Ackerman et al. discloses a non-surgical catheter device for entry into a uterus. The device includes an elongated balloon that is inserted into the cervical canal of the uterus and a tube that extends through the balloon from the eternal opening of the cervix to the internal opening of the cervix and into the uterus. By inflating the balloon, the two sections extending from the cervical canal increase in size and seal the passage through the canal. Through an opening adjacent to or at the end of the tube diagnostic fluid is dispensed into the uterus. Ackerman's device relates to uterus medical treatment procedures and does not relate to and is not able to perform controlled cervical canal dilation procedures in treated patients.
The cervical canal dilator of the present invention provides a friendly to use solution that overcomes the above mention disadvantages of the current dilators and enables controlled radial dilation of the cervix (to a predetermined diameter) within a few minutes.